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1.
Madhuri Manpadi 《Tetrahedron letters》2005,46(26):4433-4437
Various substituted arylcuprates undergo stereocontrolled additions to a d-mannitol-derived γ-alkoxy-α,β-enoate with exclusive anti-selectivity. The method is well suited for the preparation of a broad range of biologically active Amaryllidaceae alkaloids and their aromatic analogues. A model accounting for the stereochemical outcome of this process is presented. 相似文献
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Sree Madhuri A. Immadi Govardhani Venkata Narayana M. 《Wireless Personal Communications》2020,112(2):1229-1241
Wireless Personal Communications - Free Space Optical Communication Technology is expected as the successor to the existing communication technologies as many of its features like high bandwidth,... 相似文献
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M. Penchal Reddy W. Madhuri K. Sadhana I. G. Kim K. N. Hui K. S. Hui K. V. Siva Kumar R. Ramakrishna Reddy 《Journal of Sol-Gel Science and Technology》2014,70(3):400-404
Magnetic nickel ferrite (NiFe2O4) was prepared by sol–gel process and calcined in the 2.45 GHz singlemode microwave furnace to synthesize nickel nanopowder. The sol–gel method was used for the processing of the NiFe2O4 powder because of its potential for making fine, pure and homogeneous powders. Sol–gel is a chemical method that has the possibility of synthesizing a reproducible material. Microwave energy is used for the calcining of this powder and the sintering of the NiFe2O4 samples. Its use for calcination has the advantage of reducing the total processing time and the soak temperature. In addition to the above combination of sol–gel and microwave processing yields to nanoscale particles and a more uniform distribution of their sizes. X-ray diffraction, energy dispersive X-ray spectroscopy, transmission electron microscopy and vibrating sample magnetometer were carried out to investigate structural, elemental, morphological and magnetic aspects of NiFe2O4. The results showed that the mean size and the saturation magnetization of the NiFe2O4 nanoparticles are about 30 nm and 55.27 emu/g, respectively. This method could be used as an alternative to other chemical methods in order to obtain NiFe2O4 nanoparticles. 相似文献
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Syntheses of New Unsymmetrical 2,5‐Disubstituted‐1,3,4‐oxadiazoles and 1,2,4‐Triazolo[3,4‐b]‐1,3,4‐thiadiazoles Bearing Thieno[2,3‐c]pyrazolo Moiety 下载免费PDF全文
Shivaraj P. Patil Shrikant B. Kanawade Dinesh C. Bhavsar Prashant S. Nikam Sachin A. Gangurde Raghunath B. Toche 《Journal of heterocyclic chemistry》2014,51(2):368-373
New series of (thieno[2,3‐c]pyrazolo‐5‐yl)‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazoles 10a , 10b , 10c and (thieno[2,3‐c]pyrazol‐5‐yl)‐1,3,4‐oxadiazol‐3(2H)‐yl)ethanones 6a , 6b , 6c has been synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by multistep reaction sequence. (5‐Aryl‐1,3,4‐oxadiazol‐2‐yl)‐1H‐thieno[2,3‐c]pyrazoles 4a , 4b , 4c were also synthesized from thieno[2,3‐c]pyrazole‐5‐carbohydrazide 3 by cyclization with various aromatic carboxylic acids. The hydrazide 3 was obtained by reaction of thieno[2,3‐c]pyrazole‐5‐carboxylate 2 with hydrazine hydrate in good yield, and compound 2 was obtained by the reaction of 5‐chloro‐3‐methyl‐1‐phenyl‐1H‐pyrazole‐4‐carbaldehyde 1 and 2‐ethyl thioglycolate in presence of sodium alcoholate in good yield. 相似文献
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The synthesis of C1-C12 and C13-C22 fragments of (−)-callystatin A is accomplished employing desymmetrization strategy for the creation of five chiral centres of the polypropionate fragment and application of cross-metathesis (CM) reaction for the first time for this molecule. 相似文献
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The present work describes an exciting method for the selective and sensitive determination of calcitonin in human blood serum samples. Adopting the surface molecular imprinting technique, a calcitonin-imprinted polymer was prepared on the surface of the zinc oxide nanostructure. Firstly, a biocompatible tyrosine derivative as a monomer was grafted onto the surface of zinc oxide nanostructure followed by their polymerization on vinyl functionalized electrode surface by activator regenerated by electron transfer–atom transfer radical polymerization (ARGET–ATRP) technique. Such sensor can predict the small change in the concentration of calcitonin in the human body and it may also consider to be as cost-effective, renewable, disposable, and reliable for clinical studies having no such cross-reactivity and matrix effect from real samples. The morphologies and properties of the proposed sensor were characterized by scanning electron microscopy, cyclic voltammetry, difference pulse voltammetry and chronocoulometry. The linear working range was found to be 9.99 ng L−1 to 7.919 mg L−1 and the detection limit as low as 3.09 ± 0.01 ng L−1 (standard deviation for three replicate measurements) (S/N = 3). 相似文献
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Sachin A. Gangurde Shrikant B. Kanawade Prashant S. Nikam Dinesh C. Bhavsar Raghunath B. Toche 《Journal of heterocyclic chemistry》2014,51(4):883-890
Synthesis of ethyl 5‐amino‐4‐cyano‐1‐phenyl‐1H‐pyrazole‐3‐carboxylate 5 has been achieved via abnormal Beckmann rearrangement of o‐chloroaldehyde 1 . Reaction of o‐aminocarbonitrile 5 with concentrated H2SO4 furnished expected o‐aminocarboxamide pyrazole 6 . Key intermediates o‐aminocarbonitrile 5 and o‐aminocarboxamide 6 were successfully utilized for the synthesis of pyrazolopyrimidine derivatives. The replacement of Cl in o‐chlorocarbonitrile 3 with secondary amine furnished new synthon 13 , which was further used for the synthesis of polysubstituted heterocycles. The obtained new products were well characterized by IR, 1H and 13C NMR, and mass spectra. 相似文献